sys_attrs_socket

NAME

DESCRIPTION

This reference page lists and describes attributes for the Socket (socket) kernel subsystem. Refer to the
sys_attrs(5)
reference
page for an introduction to the topic of kernel subsystem attributes.

The number of lock entries to use when taking a lock reference
on an external cluster mbuf (more is better).

Default value: 0 (entries)

Minimum value: 0

Maximum value: 8192

The
mbuf_ext_lock_count
attribute is useful only
on SMP machines where locks are used.

The CPU number to which to bind the protocol timer thread.

Default value: 0

Minimum value: 0

Maximum value:
UINT_MAX, or 4 billion

Maximum size of the socket buffer.

Default value:
SB_MAX, or 128K (bytes)

Minimum value: 1

Maximum value: 4 billion

The maximum size of packets to be copied into existing
mbuf
clusters, or compressed. Only packets of size less than
sbcompress_threshold
minus 1 are copied into existing
mbuf
clusters.

Default value: 0 (bytes)

Minimum value: 0

Maximum value:
UINT_MAX, or 4 billion

If the
sbcompress_threshold
attribute value is 0,
mbuf
cluster compression is disabled.

A read-only attribute that is incremented when a received
SYN packet is dropped because the number of queued SYN_RCVD connections for
a socket is equal to that socket's backlog limit. The initial value is 0.

A read-only attribute that shows the maximum number of pending
requests to any of the server sockets in the system. The initial value is
0.

If the listen queue connection limit is too small, incoming connect
requests may be dropped. Pending TCP connections can be caused by lost packets
in the Internet or denial of service attacks.

A read-only attribute that is incremented when a received
SYN packet is dropped because the number of queued SYN_RCVD connections for
a socket is equal to the value of the
somaxconn
attribute.
The initial value is 0.

Minimum number of pending TCP connections socket listen queue
(backlog). The attribute controls how many SYN packets can be handled simultaneously
before additional requests are discardrd.

Default value: 0

Minimum value: 0

Maximum value: 65535

The value of the
sominconn
attribute overrides the
application-specific backlog if the
sominconnvalue is greater
than the backlog requested by the application. The
sominconn
value should be the same as the
somaxconn
value.

A value that enables (1) or disables (0) special socket handling
for performance improvements when transferring large files.

Default value: 0 (disabled)

A value that enables (1) or disables (0) socket writes without
the need for a user space to kernel space copy operation. The
umc
(unified mbuf cache) attribute is used in conjunction with the
mmap(2)
system call.